target/ppc: Fix rlwinm on ppc64

rlwinm cannot just AND with Mask if shift value is zero on ppc64 when
Mask Begin is greater than Mask End and high bits are set to 1.

Note that PowerISA 3.0B says that for `rlwinm' ROTL32 is used, and
ROTL32 is defined (in 3.3.14) so that rotated value should have two
copies of lower word of the source value.

This seems to be another incarnation of the fix from 820724d170
("target-ppc: Fix rlwimi, rlwinm, rlwnm again"), except I leave
optimization when Mask value is less than 32 bits.

Fixes: 7b4d326f47 ("target-ppc: Use the new deposit and extract ops")
Cc: qemu-stable@nongnu.org
Signed-off-by: Vitaly Chikunov <vt@altlinux.org>
Message-Id: <20200309204557.14836-1-vt@altlinux.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
This commit is contained in:
Vitaly Chikunov 2020-03-09 23:45:57 +03:00 committed by David Gibson
parent 52d3403d1e
commit 94f040aaec

View File

@ -1938,15 +1938,17 @@ static void gen_rlwinm(DisasContext *ctx)
me += 32;
#endif
mask = MASK(mb, me);
if (sh == 0) {
tcg_gen_andi_tl(t_ra, t_rs, mask);
} else if (mask <= 0xffffffffu) {
TCGv_i32 t0 = tcg_temp_new_i32();
tcg_gen_trunc_tl_i32(t0, t_rs);
tcg_gen_rotli_i32(t0, t0, sh);
tcg_gen_andi_i32(t0, t0, mask);
tcg_gen_extu_i32_tl(t_ra, t0);
tcg_temp_free_i32(t0);
if (mask <= 0xffffffffu) {
if (sh == 0) {
tcg_gen_andi_tl(t_ra, t_rs, mask);
} else {
TCGv_i32 t0 = tcg_temp_new_i32();
tcg_gen_trunc_tl_i32(t0, t_rs);
tcg_gen_rotli_i32(t0, t0, sh);
tcg_gen_andi_i32(t0, t0, mask);
tcg_gen_extu_i32_tl(t_ra, t0);
tcg_temp_free_i32(t0);
}
} else {
#if defined(TARGET_PPC64)
tcg_gen_deposit_i64(t_ra, t_rs, t_rs, 32, 32);